Determining Acceptable Explosive Charge Mass Under Different Geological Conditions / Problematyka Wyznaczania Dopuszczalnych Ładunków Mw W Zróżnicowanych Warunkach Geologicznych

2015 ◽  
Vol 60 (3) ◽  
pp. 825-845
Author(s):  
Józef Pyra ◽  
Anna Sołtys ◽  
Jan Winzer ◽  
Michał Dworzak ◽  
Andrzej Biessikirski

Abstract This article presents a procedure for determining the safety of explosive charges for their surrounding environment, using a limestone mine as a case study. Varied geological structures, as well as other constructions in the surrounding area of a mine, sometimes necessitate the use of two or more ground vibration propagation equations, and thus a variety of explosive charges, depending on the area of rock blasting. This is a crucial issue for the contractor, as it is important to blast the rock as few times as possible, while using the maximum amount of explosive charge for each blast.

2016 ◽  
Vol 78 (8-6) ◽  
Author(s):  
Edy Tonnizam Mohamad ◽  
Bhatawdekar Ramesh Murlidhar ◽  
Danial Jahed Armaghani ◽  
Rosli Saad ◽  
Chang Shiang Yi

Blasting operation is common method in hard rock excavation at civil engineering and mining sites. Rock blasting results in the fragmentation along with environmental hazards such as fly rock, ground vibration, air-blast, dust and fumes. Most of the common accidents associated with blasting are due to fly rock. A fly rock accident had occurred on 15 July 2015 at a construction site at Johor, Malaysia. Due to this accident, nearby factory worker was killed while two other workers were seriously injured after being hit by rock debris from an explosion at construction site, 200 m away from the factory. The main purpose of this study is to investigate the causes of fly rock accident based on geological structures and blasting practice such as blast design, pre inspection on geological structures, identifying danger zone due to blasting and communication and evacuation of personnel before blast.  It can be concluded that fly rock could have been controlled in three stages; initial drilling of holes based on blast design, ensure limiting charge for holes having less burden or having geological discontinuity, and selecting proper sequence of initiation of holes.


2021 ◽  
Vol 1 (2) ◽  
Author(s):  
Quang Hieu TRAN

Blasting is one of the most effective methods for fragmenting rock in quarries. Nevertheless, itsadverse effects are significant, especially blast-induced ground vibration. Field measurement andempirical equations are simple methods to determine and estimate the intensity of blast-induced groundvibration. However, we cannot evaluate the effects of blast-induced ground vibration on the surroundingenvironment based on these outcomes. Therefore, this study explores the relation between seismiccoefficient and rock properties through field measurements and an empirical model for evaluating theeffect of blast-induced ground vibration in open-pit mines. Accordingly, the seismic coefficient (K) isconsidered the main objective in this study. Firstly, it was determined based on the rock properties.Subsequently, an empirical model for estimating blast-induced ground vibration was developed based onfield measurements. This empirical equation was then expanded to determine K to check whether itmatches the determined K by the rock properties. Finally, it was used as the threshold to determine themaximum explosive charged per delay to ensure the safety of the surrounding environment from blastinducedground vibration. For this aim, the Thuong Tan III quarry (in Binh Duong province, Vietnam)was selected as a case study. Fifth-teen blasting events with a total of 75 blast-induced ground vibrationvalues were recorded and collected. An empirical equation for estimating blast-induced ground vibrationwas then developed based on the collected dataset, and K was determined in the range of 539 to 713 forthe Thuong Tan III quarry. Based on the measured blast-induced ground vibrations, developed empiricalmodel, and K values, the Phase 2 software was applied to simulate the effects of blast-induced groundvibration on the stability of slopes as one of the impacts on the surrounding environment. From thesimulation results, we can determine the maximum explosive charged per delay for each type of rock toensure the stability of the slope.


Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 29
Author(s):  
Mahdi Shadabfar ◽  
Cagri Gokdemir ◽  
Mingliang Zhou ◽  
Hadi Kordestani ◽  
Edmond V. Muho

This paper presents a review of the existing models for the estimation of explosion-induced crushed and cracked zones. The control of these zones is of utmost importance in the rock explosion design, since it aims at optimizing the fragmentation and, as a result, minimizing the fine grain production and recovery cycle. Moreover, this optimization can reduce the damage beyond the set border and align the excavation plan with the geometric design. The models are categorized into three groups based on the approach, i.e., analytical, numerical, and experimental approaches, and for each group, the relevant studies are classified and presented in a comprehensive manner. More specifically, in the analytical methods, the assumptions and results are described and discussed in order to provide a useful reference to judge the applicability of each model. Considering the numerical models, all commonly-used algorithms along with the simulation details and the influential parameters are reported and discussed. Finally, considering the experimental models, the emphasis is given here on presenting the most practical and widely employed laboratory models. The empirical equations derived from the models and their applications are examined in detail. In the Discussion section, the most common methods are selected and used to estimate the damage size of 13 case study problems. The results are then utilized to compare the accuracy and applicability of each selected method. Furthermore, the probabilistic analysis of the explosion-induced failure is reviewed using several structural reliability models. The selection, classification, and discussion of the models presented in this paper can be used as a reference in real engineering projects.


2020 ◽  
Vol 12 (1) ◽  
pp. 1094-1104
Author(s):  
Nima Dastanboo ◽  
Xiao-Qing Li ◽  
Hamed Gharibdoost

AbstractIn deep tunnels with hydro-geological conditions, it is paramount to investigate the geological structure of the region before excavating a tunnel; otherwise, unanticipated accidents may cause serious damage and delay the project. The purpose of this study is to investigate the geological properties ahead of a tunnel face using electrical resistivity tomography (ERT) and tunnel seismic prediction (TSP) methods. During construction of the Nosoud Tunnel located in western Iran, ERT and TSP 303 methods were employed to predict geological conditions ahead of the tunnel face. In this article, the results of applying these methods are discussed. In this case, we have compared the results of the ERT method with those of the TSP 303 method. This work utilizes seismic methods and electrical tomography as two geophysical techniques are able to detect rock properties ahead of a tunnel face. This study shows that although the results of these two methods are in good agreement with each other, the results of TSP 303 are more accurate and higher quality. Also, we believe that using another geophysical method, in addition to TSP 303, could be helpful in making decisions in support of excavation, especially in complicated geological conditions.


2012 ◽  
Vol 518-523 ◽  
pp. 5754-5759
Author(s):  
Dong Jian Xue ◽  
Zheng Wei He ◽  
Xiang Dong Zheng

Derong County is located in Ganzi Tibetan Autonomous Prefecture in southern part of Sichuan Province, in the upper of the Jinsha River, where there is a subtropical plateau monsoon climate, abundant sunshine, and large amount of evaporation, so it is a typical dry-hot valleys region. Derong County is the area of more ups and downs in the terrain, deep valleys, steep mountains, complex geological conditions, intense tectonic activity, various climate types, and has obvious vertical zone effect by temperature, serious physical weathering of rock, and landslide, debris flow, collapse and other geohazards are easily induced under the influence of rainfall and human engineering activities. These geohazards have brought serious harm to the people's lives and property, and have a great impact on the socio-economic development. Through the analysis of geohazards in the study area to investigate its distribution and development trends, this paper provide a basis for geohazard prevention and economic development.


1997 ◽  
Vol 87 (2) ◽  
pp. 356-369
Author(s):  
Takumi Toshinawa ◽  
J. John Taber ◽  
John B. Berrill

Abstract The areal distribution of seismic ground-motion intensity in the city of Christchurch, New Zealand, during the 1994 Arthurs Pass Earthquake (ML 6.6) was evaluated using an intensity questionnaire together with local site amplifications inferred from seismic recordings and microtremors. In order to estimate the intensity in parts of the city where no intensity data were available, intensity data were compared to relative levels of shaking determined from both weak-motion and microtremor recordings. Weak ground-motion amplification factors were determined using ratios of ground accelerations at five sediment sites with respect to a rock site. Microtremor amplification factors were determined from horizontal-to-vertical spectral ratios at a 1-km spacing throughout the city. A positive correlation between weak-motion and microtremor amplification factors allowed extrapolation of microtremor amplification to estimated MM intensity (EMMI). EMMI ranged from 3 to 6 and was consistent with the questionnaire intensity and geological conditions and showed detailed information on the areal distribution of ground-motion intensity in the city.


2020 ◽  
Vol 12 (23) ◽  
pp. 10152
Author(s):  
Joel T. Betts ◽  
Juan F. Mendoza Espinoza ◽  
Armando J. Dans ◽  
Christopher A. Jordan ◽  
Joshua L. Mayer ◽  
...  

The practice of harvesting fish and crustaceans by using pesticides is understudied and under-reported in tropical inland fisheries yet poses a significant threat to freshwater biodiversity and community health. This research provides a brief review of the practice and an in-depth case study from southeast Nicaragua. In 2019, 86 interviews and 5 focus groups were conducted in remote communities in the Indio Maíz Biological Reserve (IMBR) and nearby surrounding area and combined with 4 years of local Indigenous Rama and Afrodescendent Kriol community forest ranger data. Forest rangers and 74% of interviewees reported that fishing with pesticides occurs in their communities, including both inside the IMBR and in the nearby surrounding area. The practice is primarily used by illegal settlers, and not by Rama and Kriol communities who have rights to the land in the IMBR. It entails the release of liquid pesticides in water or mixing powdered pesticides with corn flour and using the mixture as bait. Of seven chemicals reported, Cypermethrin, Deltamethrin, and Aluminum Phosphide were most common. The use of ichthyotoxic woody plants was more rarely reported. Habitats targeted ranged from swift headwaters to slow pools in small creeks to larger rivers, depending on target species. Main uses reported for the catch were food for family, bait to catch larger fish, and for sale. The main motivation was increased catch efficiency. Many interviewees attributed stomach issues, diarrhea, cough, convulsions, and miscarriage to exposure to poisoned river water. Twenty-five interviewees blamed poisoned rivers for livestock miscarriages or death. Severe local losses of fish and shrimp populations were reported. Rama and Kriol interviewees describe the practice as a threat to their river-based food security. Despite its illegality, no study participant knew a case of pesticide fishing that had been prosecuted. This destructive fishing practice has significant implications for conservation of the intact river systems of the primary rainforests of southeast Nicaragua, and to the local traditional fisheries they support.


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